The HTC One (M8) is one of the most popular Android smartphone of 2014. The phone is available from nearly all major service providers, but you will need to SIM unlock the HTC One (M8) if you already own the phone and want to switch service. While there are paid services like HTC SIM Unlock which will send you the unlock code for your HTC One (M8) for as little as $12.95, we thought we’d put together a simple guide which walks you through three options which allow you to SIM unlock the phone for free.

Option 1 – carrier unlock code request

Believe it or not, the best easiest way to get your hands on a SIM unlock code for your HTC One (M8) is calling your service provider and simply asking for it. It’s that simple. Most service providers require that the phone is paid in full or that you’re at least 18 months into your 24 month contract. Check with your service provider for their exact requirements. If you do not meet the criteria required by your service provider, the following two options may work for you.

Locate your handset IMEI number by dialing *#06#

Write down your IMEI number

Call your service provide and ask customer service for the SIM unlock code for your HTC One (M8)

Customer service use your IMEI number to process the unlock code request for your HTC One (M8)

Your HTC One (M8) unlock code will be emailed to you in 1-3 days

Insert a nanoSIM card from another service provider into the phone

When prompted, enter the HTC One (M8) SIM unlock code

Enjoy!

Option 2 – super CID (warning: will void your warranty)

This SIM unlock option for the HTC One (M8) is a little technical, but it’s a great alternative for those who already have an s-off HTC One (M8). Changing the CID on your phone essentially changes the region status of your phone. Changing the CID to the right number will trick the phone into thinking it’s already unlocked. This will allow you to use a SIM card from another service provider in your HTC One (M8) without entering a SIM unlock code.

Option 3 — universal SIM unlock (warning: will void your warranty)

Those who don’t want to mess with the CID of the HTC One (M8) can also try the s-off universal SIM unlock option. The first half of the process is just as technical as option 2, but things get easier after that. You do have to trust SIEEMPI with your email and IMEI number, but we have not heard of any privacy concerns form anyone who’s used this method.

Fill out the form on SIEEMPI with your IMEI, phone model and email address. A unique file for your HTC One (M8) will be emailed to you

Download the config.dat file in root of your microSD card.

Reboot into bootloader mode (press and hold volume down + power buttons).

In bootloader mode use the volume keys to highlight SIMLock, press the power button and the config.dat file will be applied.

Follow the prompts on the screen and reboot your phone.

Insert a nanoSIM card from another service provider into the phone

Enjoy!

The simple, paid alternative

If you don’t meet your service provider’s SIM unlock requirements or don’t want to void your warranty and risk bricking your phone, there is a fourth option that’s quick and hassle free. There are dozens of SIM unlock services on the web like HTCSimUnlock.com that can unlock your HTC One (M8). Like your service provider, all they need is the IMEI number for your phone and they will usually send you the unlock code in less than 30 minutes. Most SIM unlocking services even have a money-back guarantee if they are not able to locate the SIM unlock code for your HTC One (M8).

If you know if any other free options to SIM unlock the HTC One (M8), please let us know if the comments below.

Nick is a tech enthusiast who has a soft spot for HTC and its devices. He started HTCsource.com (the first HTC blog) back in 2007 and later joined the Android and Me family in the summer of 2010.

Nope, the Samsung does not have HBOOT (a bootloader designed by HTC) – which HTC has. Hboot is used for fastboot flashing, recovery and more!

I sold my HTC One for a S5 and its the worse choice ever (laged on first day, updates did very LITTLE change – try screen mirroring and playing a 3d game – LAG. Try it on the HTC One with the Media Link HD; way better – need to say that no apps are running at it uses 1.3gb ram out of 2gb – probably samsung spyware running…)

The S5 doesn’t have 4.4.3 yet and its the latest flagship! The HTC One is a year later and has 4.4.3 – and a official unlocking bootloader website unlike Samsung which requires third party programs and hacks…

Went with the HTCSimUnlock.com option since I’m not quite ready to void the warranty on my phone and it’s not yet paid off on T-Mobile. Process is simple and got an email with the code in less than 10 minutes.

Now, off to Europe for a few weeks! Anyone have a suggestion for a great service provider in France and Italy with cheap data while in there?

I figured that much and went with the guys from simlockexpress. I just fallowed this tutorial here and code the unlock code in minutes: http://www.simlockexpress.com/2014/10/how-to-unlock-insert-unlock-code-in-htc-one-m8/
Hope it helps you guys, for those who are not so gifted to rooting and messing up your phones. They gave me a little code that i inserted in my htc one m8 and done, i was using t-mobile sim in a metter of minutes.

I have tried both sites to unlock my appreciated htc one m8, unfortunately, both sites never send my the unlock code. What i recommend ? My recommendation is to go for an official htc unlocking service.

I have a HTC One M8 locked to Sprint that I bought on ebay and wanted to use outside the US.
Weirdly, when I enter *#06# I do not get any answer from the phone.
I know the IMEI number, because it is on the box.
And the unlock code I bought from internet is useless, since I am not asked for an unlock code when I use a different SIM card than Sprint.

Any idea, what I could do, to force the phone to ask for the unlock code (that I already have)?

it sounds Sprint has locked down their version of the HTC One (M8), removing the SIM unlock screen when a different SIM card is entered. Best thing to do is to call Sprint to see if there’s something they can do on their end.

did you get your unlock code? i have htc one m8 sprint lock in saudia but it shoing invalid sim only not asking for any type of code. 2ndly when i dial *#06* its never show imei number but i know its imei numbr
plz help me
thanks

Can someone please please please help.. I hav the same problem and I find this same question all over the net. Wat I am not finding is an answer,NOWHERE. Thr has to be sum1 out thr that knows the solution.what gives.help us.I love this HTC one phone ,and so want to put it to use .I hav code .I need a place to enter it on HTC ONE. If u find solution could u plz post and I shall do the same,on evry web site ,blog, or, forum that mentions HTC. This is ridiculous and veeery frustrating.

Did you ake the s-off and all the process described?? if not I recomendo you to do the s-off with firewater, then change the cid and try. If this option didnt works, try the third option discribe into the article. about use the wbe site provide to make the sim unlock. Hope helps

Did you make the s-off and all the process described?? if not I recomend you to do the s-off with firewater, then change the cid to super cid and try again. If this option didnt works, try the third option described into the article. about use the web site provided to make the sim unlock with the dile .dat. Hope helps

Why you don’t use https://www.officialhtcunlock.com/ ? It is fastest and easiest way to SIM unlock the HTC One M8. They just ask your email and your IMEI, they send me the unlock code in less than 10 minutes to my email. I hope I help you to SIM unlock your phone.

I’ve just unlocked a HTC One M8 locked initially on Orange Romania in a few hours using a unlock code provided by http://www.decodare.info Highly recommended to anyone with HTCs locked on romanian networks and not only… They will answer very quick to english written emails. Cheers, Mike.